1. Field of the Invention
The present invention relates to power supply systems and more particularly, to a power transmission method of high-power wireless induction power supply system, which employs frequency modulation technique and multi-array architecture to regulate the Output power subject to the condition of the load, ensuring high level of safety and efficiency in wireless power transmission.
2. Description of the Related Art
Following fast development of electronic and internet technology, many digitalized electronic products, such as digital camera, cellular telephone, multimedia player (MP3, MP4) and etc., have been continuously developed and have appeared on the market. These modern digital electronic products commonly have light, thin, short and small characteristics.
However, for high mobility, power supply is an important factor. A mobile digital electronic product generally uses a rechargeable battery to provide the necessary working voltage. When power low, the rechargeable battery can be recharged. For charging the rechargeable battery of a digital electronic product, a battery charger shall be used. However, it is not economic to purchase a respective battery charger when buying a new mobile electronic product. Further, when one uses a big amount of money to purchase different mobile electronic products, a special storage space is necessary for the storage of the mobile electronic products. Further, it is inconvenient to carry and store many different mobile electronic products and the related battery chargers.
In view of the aforesaid problems, wireless induction power supply systems are created. However, most commercial wireless induction power supply systems are for low power application, for example, for use in a mobile telephone or digital camera. There are certain high-power wireless induction power supply systems for use in high-power electronic apparatus, such as notebook computer. However, these high-power wireless induction power supply systems have drawbacks as follows:
1. During operation, the circuit board and its electronic components generate much waste heat, and the power-transmitting coils will also product heat, increasing safety risk.
2. The circuit architecture includes power switch means and resonance capacitor means that operate at a high frequency. Due to technical limitations, conventional techniques cannot fabricate a high-power power switch that operates at a high frequency for high power output. Even if a high-power power switch that operates at a high frequency for high power output is available, the manufacturing cost will be extremely high. The fabrication of resonance capacitor encounters the same problem.
3. The wireless power-transmitting and power-receiving induction coils of a high-power wireless induction power supply system must be accurately aligned. Further, the output electrical energy is fixed and not adjustable subject to the condition of the load. Therefore, conventional high-power wireless induction power supply systems have a low performance.
4. Conventional high-power wireless induction power supply systems are commonly designed to let the induction coil of the power-receiving end receive a voltage higher than the demand of the target at first and then to let the voltage be lowered to the level of the demand of the target by a DC-DC Step-Down IC. However, because voltage-down is achieved through switch means, energy loss will occur and interference noise and waste heat will be produced during each switching operation.
Therefore, it is desirable to a power transmission method for high-power wireless induction power supply system that eliminates the aforesaid problems.